• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.126-129
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• 2003

A relatively high homology between Escherichia coli prolidase and Alteromonas organophosphorous acid anhydrolase suggests that E. coli prolidase may have an activity to d egrade toxic organophosphorous compounds. To confirm this suggestion, we cloned and expressed a prolidase gene (pepQ) of E. coliBL2l. The recombinant E. coli prolidase that consisted of 443 amino acid residues exhibited activity and stereochemical selectivity against organopho sphorous compounds, although its activity was two to three orders of magnitude less than that of the other organophosphorous acid hydrolase isolated from Pseudomonas diminuta.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.183-183
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• 2003

In recent years, organophosphorous (OP) pesticides have largely replaced the use of organochlorine pesticides and have been widely used in agriculture because of their rapid breakdown in water and their low environmental persistence. Consumers are directly or indirectly exposed to organophosphorous pesticides through several food groups in which a significant amount of pesticide residues have been found.(omitted)

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.326-332
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• 1999

Background: In korea the agricultural community widely uses organophosphorous, and organophosphorous poisonings are increasing every year. We compared change in activity of acetylcholinesterase and pseudocholinesterase by organophosphorous and by the interaction of ethanol and organophosphorous. We also compared the effect of reversible anticholinesterase drugs, physostigmine and neostigmine The object of this study is to investigate the effects of several anticholinesterase drugs and on how ethanol influences the activity of cholinesterase. Materials and Methods: Fifteen male university students were randomly selected, and blood samples were taken from the antecubital vein. The acetylcholinesterase in the RBC and the pseudocholinesterase in the serum were extracted and separated. The enzyme activity change was measured by the electrometric method. After adding acetylcholine, the pH change was measured with a pH meter. Results and Conclusion: Our results indicated that reversible anticholinesterase drugs decreased the cholinesterase activity more efficiently than organophosphorous. The acetyl cholinesterase and pseudocholinosterase activity were decreased by ethanol. When ethanol was added, oxime a cholinesterase activator, increased acetylcholinesterase activity but does not increased pseudocholinesterase activity.

• Journal of Preventive Medicine and Public Health
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• v.25 no.2 s.38
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• pp.180-188
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• 1992

The effects of multiple exposures to pesticides on plasma cholinesterase(ChE) activities and urinary p-nitrophenol excretion were evaluated in rats. Rats were received single dose i.p. with $LD_{50}/100(mg/kg)$ of organophosphorous(OP), organophosphorous-organochroline(OP-OC), organophosphorous-carbamate(OP-CAB), organophosphorous-organoarsenate(OP-OA) pesticides for 4 consecutive days. In repeated administration of pesticides, plasma ChE activities were decreased, but urinary p-nitrophenol were increased after the first injection and then decreased gradually The recovery rates of ChE activities and p-nitrophenol excretion at 48 hours after the fourth Injection were delayed in comparision with the baseline value of 24 hours before the first injection. Statistical significances were found between OP and other groups except OP-OA group after the second injection in plasma ChE activities, but in urinary p-nitrophenol excretion there was statistical significance only between OP and OP-CAB.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.183-183
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• 2003

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.05a
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• pp.78-79
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• 2003

• Environmental Analysis Health and Toxicology
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• v.2 no.1_2
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• pp.17-24
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• 1987

Changes in cholinesterase (ChE) activity, electrophoretic pattern of ChE and histopathologic state on the mice serum, brain and liver by administration of organophos-phorous insecticides were studied. The mice ChE activities on serum, brain and liver decreased by increasing of concentration and time both administration of malathion and DDVP, whereas on serum and brain the activities of the 7 days after administration decreased, and then presented the gradually slight recovery in course of time. The ChE on serum and liver showed many isozyme bands by polyacrylamide gel electrophoresis but several on brain. And isozyme bands disappeared and diffused by administration of organophosphorous insecticides and development of time. The mice liver with administration group of malathion on histopathologic test showed midzonal necrosis between central vein and portal area, and with administration group of DDVP mainly presented portal necrosis on location of potal area.

• Journal of Environmental Science International
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• v.11 no.6
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• pp.589-596
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• 2002

Photocatalytic degradation of chlorpyrifos and diazinon, which are extensively used as an organophosphorous pesticide in the agriculture field, has been investigated with UV-radiated TiO$_2$ in aqueous phase. Photodegradation rate was increased with increasing pH of the solution. The removal efficiencies of chlorpyrifos and diazinon were 100% after 200 min in pH 9. Photodegradation followed a pseudo-first-order reaction. The rate constants of chlorpyrifos and diazinon were 0.0160min$\^$-1/ and 0.0180min$\^$-1/, respectively. NO$_3$$\^$-/, PO$_4$$\^$3-/, SO$_4$$\^$2-/ and Cl$\^$-/ were found as end products on the photocatalytic degradation of chlorpyrifos and diazinon with TiO$_2$/UV.

• 한국해양학회지
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• v.25 no.1
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• pp.21-25
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• 1990

Eleven water samples were analyzed for organophosphorous pesticides in Suncheon Bay with Gas Chromatography Mass Spectrometry. For the first time in Korea, Kitazin-P was found in marine environment and the concentrations ranged upto 2.2mg/l. The regional and temporal variations of the pesticide were also studied.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.78-79
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• 2003

Organophosphorus (OP) pesticides have largely replaced the use of organochlorine pesticides and have been widely used in agriculture and houses in recent years because of their rapid breakdown in water and their low environmental persistence. As a result, consumers are directly or indirectly exposed to organophosphorus pesticides through several food groups including meat, dairy products, fruits, vegetables, dried foods, and most processed food in which a significant amount of pesticide residues have been found.(omitted)